1. Field of the Invention
The present invention relates to a trailer lamp controller which is useful in connecting a plurality of electrical circuits of turn and brake lamps of a towing vehicle to a plurality of electrical circuits of turn and brake lamps of a towed vehicle.
2. Description of the Prior Art
The need for electrically connecting circuits of a first vehicle to circuits of a second vehicle is well known. For example, when a trailer is hitched to an automobile it is desirable to connect various automobile lighting circuits to corresponding trailer lighting circuits. In particular, it is desirable to connect the automobile brake light circuit and turn signal circuit to corresponding trailer light circuits. Heretofore, one known manner by which the electrical connection of trailer lamps to a towing vehicle has been effected is by tapping a connector into the wiring of the towing vehicle lamps and then connecting the trailer lamps directly to such connector. With the various domestic and foreign lighting, wiring and control systems presently in use, a variety of types and designs of connectors have been required. Some of the known systems having required the use of solid state and mechanical relay parts. The degree of success of such different connectors has varied with some connectors not functioning properly, if at all.
Efforts have been made to provide a more standard connector. For example, efforts have been made using components such as phototransistors, photoresistors, photodiodes, and the like to sense the light from the lamp of a towing vehicle and using such sensed light to actuate a corresponding lamp in a trailer. However, problems have been encountered due to the presence of false indications from extraneous light sources such as the sun and headlights of other vehicles. In addition, the use of such light sensing components requires the presence of corresponding electronic circuitry which presents further problems with reliability and adds to the cost of producing such apparatus.
It is highly desirable to provide a trailer lamp controller for connecting electrical circuits of a towing vehicle to corresponding electrical circuits of a towed vehicle which can be used with the lighting, wiring and control systems of any domestic and foreign vehicle. It is also desirable to provide such a controller which does not require the use of solid state in combination with mechanical relay parts. It is further desirable to provide such a controller which does not rely upon the use of light sensing components in combination with corresponding electronic circuitry. It is further desirable to provide such a controller which functions independent of the presence of light and which therefore is not adversely affected by any extraneous light sources. It is also desirable to provide such a controller which will be operative whether plus or ground is switched. It is further desirable to provide a relatively inexpensive device for use as described herein having few components and improved reliability. It is also desirable to provide such a device for use with a towing vehicle having separate and distinct turn and stop lamp filaments and a towed vehicle having the same filament for turn and stop signals.